1. We use the Future Perfect Continuous to show that something will continue up until a particular event or time in the future. “For five minutes”, “for two weeks” and “since Friday” are all durations which can be used with the Future Perfect Continuous.

Examples:
1. I will have been waiting for him for one hour.
2. She will have been playing football since 2015.

Rule For How To Make Tense:

If Sub=I, You, Singular(एकवचन) or Plural(बहुवचन)[Same Rule for all Subjects]